This content has been marked as final. Show 28 replies
Uncompressed AVI at whatever your project settings are.
Thank you for the input, however, from my few experiments with uncompressed AVI I noticed that the file sizes are enormous (over a gig for a several seconds clip)--whereas, in my understanding, HDV should be just over 2 gigs for a 10min clip (since a 1hr tape is about 13gigs)
Am I missing something?
Video editor you want the best quality but at small sizes... does not exist, pick one.
Buy more/bigger hard drives.
I'm afraid I wasn't clear... If the original footage captured was HDV quality, would I be correct in saying that exporting uncompressed would yeild unnecessarily large files (since the original footage was compressed)?
What I'd like to do is simply get just what I put it; that is, HDV.
Here is what I mean:
(from the Premiere CS3 user manual)
"STANDARD EXPORT COMMANDS: The standard export commands (Export > movie...) are used to export full-resolution files that can be archived or brought into projects for further editing. (...)
i Initially, the settings for standard export match the Project settings,
b except in HDV projects which use DV settings by default."
What I don't understand is WHY would Premiere only offer DV settings by default for HDV projects--why not HDV?? Does this not mean that the HDV footage you have shot and captured would be recompressed in DV quality (which is much lower) upon export?
I have tested the DV-AVI format with Premiere 2.0 and found the quality to be lower than even H.264 compression...
Is there not a way to export HDV footage at HDV quality, and if not, what's the point of going through the process of working with HDV to begin with...?
I hope that someone might shed some light here, because I'm completely lost...
Yes, there is a way to export to HDV quality. There will be some decrease in the quality over the original because there is no way to just re-encode the changed frames. That is due to the Long GOP nature of the beast.
However, you will probably be happy with exporting to SD, or to any size other than HD, and the format is already HD, so just copy the file.
The solution is to use MPEG2 Blu-ray High Quality at the correct frame rate. Set quality up from 4 to 5 if there is any serious motion in the footage. You can't use PCM if you multiplex the audio with the video, so deal with two files.
This footage is exactly like HDV, so you can even use it in a HDV project without rendering when you want to use the Adobe Media Encoder to create something else.
Be aware that the scaling from HDV to SD is much better in CS3 than in was in 2.0
>what's the point of going through the process of working with HDV to begin with...?
Someone's getting it.
> What I'd like to do is simply get just what I put it; that is, HDV
Then export MPEG 2 out...
Thanks for all the feedback!
i "There will be some decrease in the quality over the original because there is no way to just re-encode the changed frames. That is due to the Long GOP nature of the beast."
This made me think... I'm assuming the reason you're saying that it's impossible to just re-encode the changed frame is because with GOP there are very few true whole frames, while the rest are being constructed at real time; now, would that still be the case if I were to first capture the footage using a lossless codec, and then import it into the time line? Because I'm thinking that perhaps, since the latter is actually composed of true frames, there is no reason why premiere could not re-encode only the changed ones... Thoughts?
Also, could you please explain the following (as I'm not sure I understand correctly which format you are referring to, as well as where to/how should I copy the file...)
i However, you will probably be happy with exporting to SD, or to any size other than HD, and the format is already HD, so just copy the file.
am I correct to understand you are convinced that working with HDV is a futile effort? If so, could you please elaborate a bit on your conclusion?
I actually thought about exporting MPEG 2 out myself the other day--two questions:
1. I read that HDV utilizes a
of MPEG 2 compression; would the MPEG 2 export option offered by adobe premiere be exactly the same, or could it be the same genral method, yet different in some ways?
2. Supposing that it is exactly the same compression method as HDV, would premiere not re-compress again the entire sequance if I were to export the project in MPEG 2, resulting again in lower quality?
You seem to want avoid the issue...
There is no way to get your original quality without having large file sizes or without compressing it slightly... Like I said pick one.
The MainConcept MPEGPro plug-in allows unchanged frames to avoid recompression, but that is for file export only. Export back out to tape requires full recompression of every frame. That's because of the required long GOP structure that must exist on an HDV tape.
When working with DV/AVI only the frames which are filtered/transitioned are re-rendered; all of the "untouched" frames are simply copied so there's no recompression of these.
So if I understand correctly, when you export HDV, Premeier can't do the above, and ALL of the exported footage gets re-MPEG-compressed even if none of it was filtered or transitioned at all?
Although HDV uses a long GOP structure, you might imagine that Premiere could re-render only those GOPs where frames had been filtered, and copy (without re-compressing) all of the other GOPs (possibly changing the timestamps if necessary).
>if I were to first capture the footage using a lossless codec
Well, lossless is a bit too large to deal with but Cineform Aspect HD uses a visually perfect conversion. That solves the problem.
It has all of the info in every frame.
>so just copy the file
The MPEG2 Blu-ray setting is exactly what you need to put on a Blu-ray disk so when you are ready, you have a file you can use. In the meantime, it is the same as the HDV you captured (with a little loss) so any conversion to a smaller frame size will in all liklihood hide any loss.
>am I correct to understand you are convinced that working with HDV is a futile effort?
No not futile. People do it every day. I'm just not a fan of temporal compression in source material is all, so I took the opportunity to throw in a little jibe. You can safely ignore me on this one.
I'm confused.... My impression is what Jeff said, that file export may avoid full recompression of every frame, but that it is export to HDV tape that involves the long GOP problem. But Harm responded "yes" when Colin asked, "...when you export HDV, Premier can't do the above [referring I think to "only the frames which are filtered/transitioned are re-rendered"], and ALL of the exported footage gets re-MPEG-compressed even if none of it was filtered or transitioned at all?"
Jeff's comments suggests a "no" for file export and "yes" for tape export. (And Jeff, did this change with CS3?)
Colin went on to say "Although HDV uses a long GOP structure, you might imagine that Premiere could re-render only those GOPs where frames had been filtered, and copy (without re-compressing) all of the other GOPs (possibly changing the timestamps if necessary)." That is true, except that the "long GOP" (I think) means that you cannot have unequal GOP lengths and so, once one GOP gets rendered, you can never catch up.
Am I missing something?
Jeff's comment was made in reference to using the $450 MainConcept plug-in for Premiere. Premiere on it's own cannot export out HDV without recompressing every frame.
On further thought, because HDV used a fixed-size GOP, if you want (say) a cross-fade with frame accuracy then this could break the fixed-GOP size cadence, which would in theory ripple forward through the entire output. Maybe this is one reason why Premiere re-renders the whole footage. If the HDV specs allowed a deviation from fixed GOP size to cover situations like this then it would make it easier to re-render only particular GOPs.
Incidentally, does anyone here use the free lossless intra-frame codec Lagarith as an alternative to Cineform?
Jim's analysis of my post is correct.
Thanks, Jim and Jeff, for the clarification.
Colin asks about the effect of breaking the fixed-GOP size cadence and the ripple effect to the end of the clip. He wonders if "this is one reason why Premiere re-renders the whole footage." My understanding was that a "non-frame-accurate" mpeg editor was reencoding the entire clip, whereas a frame accurate editor was encoding only the gops that changed, changing the length of one or more gops so that there was no re-encoding before or after the effected gops. I don't think I ever got confirmation, but it appeared that PPro reencodes the entire clip, without regard to any changes. Is that the situation with PPro?
Given the HDV spec, I don't see any option other than leaving the gops before a change alone, but you have to reencode all those that follow, unless you are only editing on gop breaks.
>it appeared that PPro reencodes the entire clip, without regard to any changes. Is that the situation with PPro?
On it's own, yes.
I apologize for re-asking the same question, but would this still be the case if one was to use a lossless codec first--or would premiere be able to treat only the changed frames by virtue of having whole frames to work with rather than the initial GOPs?
(From my understanding, a lossless codec reconstructs all the frames and generates a new clip composed of whole frames rather than GOPs)
Please correct me if I'm wrong, thanks!
Lossless codecs are generally all I-Frame, or rather, "whole frames". So there is no recompression problem.
Here's a step by step of how I deal with it:
FILE> EXPORT> ADOBE MEDIA ENCODER
Preset: 1440 X 1080i 29.97 High Quality
I've had terrific results. Have no idea if it is recompressing every frame, but the speed of the processing leads me to believe it isn't. What matters to me is that I don't see any 2nd gen artifacts, and it preserves the format that was captured.
Best of Luck!
Thanks for the input!
I followed your advice (with the exception of choosing 1920x1080 for output to get square pixels). The video looked good, however, I did not get any sound--what sound settings do you choose?
Also, do any of you know whether CS3 has an issue with capturing HDV out of sync as well?
The audio is in a separate WAV file unless you told it to multiplex.
CS3 version 3.2.0 solved the out of sync problem.
Would multiplaxing cause any loss in quality?